What is the average weight for an eight week old puppy? And how many calories per pound of body weight do they require?

I like to look at them and decide what they need to be having as far as calories go, but I do have a general guideline that I like to use to see where they fit on the chart. I almost always am feeding them what is suggested on the chart.

The chart says a 15 lb. 8 week old pup should be getting 1125 cal. and a 20 lb. 8 week old should get 1500.